Just wanted to post this because I discovered this recently... I was cutting an interview and had the audio running through a Submix Track (bus) with a bunch of effects on it. All the effects were running through the Audio Track Mixer Window. However, I noticed that when I was cutting my selects, I was getting a very glitchy/stuttery playback. It wasn't terrible when I was in normal speed, but when I jumped to 2x speed, the audio became so warbled and stuttery, I couldn't even understand what was being said.

I checked all my settings and everything seemed to be looking good: Audio hardware was set up correctly, was using Open CL, sequence settings was using prores not i-frame. I tried a bunch of different things but I realized that the effects running on in the Audio Track Mixer window were causing the problem. As soon as I turned those off, my problem went away. This isn't a huge inconvenience to me, as I can make my selects still, but I thought I'd throw it out there to see if there's some geniuses who know what's going on with all that...

Settings....

Footage was shot on ARRI ProRes 422 HQ

Audio was recorded straight to camera

Shotgun mic (XLR in) and Lav mic (XLR)

I did a Multi-cam sequence to sync multiple cameras

I wanted to clean up the audio a bit so I ran it through my standard clean up. (I usually use the Track Mixer Effects because the noise reduction samples the audio from the track as a whole and not the particular clip which usually gives me a better result).

Track 01 & 02 (Audio from camera). Instead of this going to the Master Track, I set it to go to a Bus (Submix Track) where I added the following effects: